Preheat & prep: Preheat oven to 180°C fan. Grease and line your cake tins.

Chocolate shards: Using a potato peeler, peel strips from the side of a chocolate bar onto baking paper. Refrigerate once you have five or six curls.

Dry ingredients: Add flour, caster sugar, brown sugar, salt, bicarb and baking powder to a stand mixer fitted with a paddle attachment. Mix until evenly combined.

Cocoa paste: Make 2 shots of espresso and weigh 85 g into a bowl. Whisk in the cocoa powder until smooth, then add the crème fraîche and orange zest. Whisk again to a smooth paste.

Combine: Add the eggs, oil and half the cocoa paste to the dry ingredients. Mix on low until combined, then add the remaining cocoa paste. Beat until the batter is smooth.

Bake: Divide the batter evenly between three prepared tins. Alternatively, use one tin and slice the cake into three layers once baked and cooled. Reduce oven to 170°C and bake. Allow to cool for at least 5 minutes, remove from tins onto a cooling rack, then refrigerate.

Soak the gelatine in cold water with a few ice cubes for 5 minutes. Whisk the sugar, cocoa powder and water in a saucepan to form a paste, then add the cream. Bring to the boil for 1 minute. Remove from heat, stir in the drained gelatine and strain through a sieve into a clean jug. Press cling wrap onto the surface and set aside.

Place egg whites, sugar, salt and cream of tartar in a metal bowl over a double boiler. Stir until the mixture reaches 72°C. Transfer to a stand mixer fitted with a whisk attachment and whisk to stiff peaks until the meringue cools to 30°C.

Meanwhile, melt the dark chocolate over the simmering water. Cool to 30°C. With the mixer running, add the butter to the meringue a few cubes at a time until fully incorporated. Add the melted chocolate and orange zest and whisk until combined.

Juice the two zested oranges and weigh the juice. Add to a saucepan with the same weight of caster sugar. Bring to a simmer, stirring until the sugar dissolves. Remove from heat and set aside.

Layer: Trim the sponges so they are flat and of equal height. Place one layer on a plate and dab liberally with orange syrup. Dab the inside of the remaining layers too. Spread buttercream between each layer. Cover the entire cake with the remaining buttercream and smooth with a cake scraper. Freeze until firm.

Glaze: Place the cake on a cooling rack over a large plate. Gently reheat the glaze in the microwave to 24°C and strain through a sieve into a jug. Pour evenly over the cake. If coverage is uneven, collect the glaze from the tray, reheat to 24°C and repeat. Allow to set in the fridge for a few minutes, then carefully transfer to a serving plate using two offset spatulas.

Finish: Top with chocolate curls and fresh orange segments.